Introduction

Ever since Edward Snowden leaked classified details about the National Security Administration’s surveillance programs, Americans have grown increasingly concerned about government infringement on their right to privacy. The concept of a constitutional right to privacy is nothing new, but its boundaries are often nebulous.

The Supreme Court has been weighing the limits of privacy rights since 1965, when it issued a landmark ruling in Griswold v. Connecticut, which held that Connecticut’s ban on the use of contraceptives violated the right to marital privacy. In his dissenting opinion, Justice Hugo Black noted that privacy “is a broad, abstract and ambiguous concept.” But despite Black’s concerns, privacy has since become a fundamental protection in our Constitution that many Americans treasure. Just eight years later, in one of the court’s most contentious and important cases, Justice Blackmun argued in Roe v. Wade that the 14th Amendment right to privacy protected a woman’s right to have an abortion.

Since the Griswold case, the Court has regularly taken up new privacy issues as technology evolves. In some cases, the Court has chipped away at the zone of privacy, giving the green light to schools that make choir students consent to drug tests. In others they have codified new privacy rights, such as forcing police to obtain a warrant before allowing drug-sniffing dogs to track down marijuana growers in their homes.

To trace how the Supreme Court has defined privacy, TIME takes a look back at five recent privacy cases: